| Fungal hydrophobin | |||||||||
|---|---|---|---|---|---|---|---|---|---|
 Structure of hydrophobin HFBII from Trichoderma reesei | |||||||||
| Identifiers | |||||||||
| Symbol | Hydrophobin_2 | ||||||||
| Pfam | PF06766 | ||||||||
| InterPro | IPR010636 | ||||||||
| PROSITE | PDOC00739 | ||||||||
| SCOP2 | 1r2m / SCOPe / SUPFAM | ||||||||
| OPM superfamily | 96 | ||||||||
| OPM protein | 1r2m | ||||||||
| |||||||||
| Hydrophobin | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| Symbol | Hydrophobin | ||||||||
| Pfam | PF01185 | ||||||||
| InterPro | IPR001338 | ||||||||
| |||||||||
Hydrophobins are a group of small (~100 amino acids) cysteine-rich proteins that were discovered in filamentous fungi that are lichenized or not. Later similar proteins were also found in Bacteria.[1] Hydrophobins are known for their ability to form a hydrophobic (water-repellent) coating on the surface of an object.[2] They were first discovered and separated in Schizophyllum commune in 1991.[3] Based on differences in hydropathy patterns and biophysical properties, they can be divided into two categories: class I and class II. Hydrophobins can self-assemble into a monolayer on hydrophilic:hydrophobic interfaces such as a water:air interface. Class I monolayer contains the same core structure as amyloid fibrils, and is positive to Congo red and thioflavin T. The monolayer formed by class I hydrophobins has a highly ordered structure, and can only be dissociated by concentrated trifluoroacetate or formic acid. Monolayer assembly involves large structural rearrangements with respect to the monomer.[4]
Fungi make complex aerial structures and spores even in aqueous environments.
Hydrophobins have been identified in lichens[5] as well as non-lichenized ascomycetes and basidiomycetes; whether they exist in other groups is not known.[6] Hydrophobins are generally found on the outer surface of conidia and of the hyphal wall, and may be involved in mediating contact and communication between the fungus and its environment.[7] Some family members contain multiple copies of the domain.
Hydrophobins have been found to be structurally and functionally similar to cerato-platanins, another group of small cysteine-rich proteins,[8] which also contain a high percentage of hydrophobic amino acids,[6] and are also associated with hyphal growth.[9][10]
This family of proteins includes the rodlet proteins of Neurospora crassa (gene eas) and Emericella nidulans (gene rodA), these proteins are the main component of the hydrophobic sheath covering the surface of many fungal spores.[11][12]
Genomic sequencing of two fungi from dry or salty environments (Wallemia sebi and W. ichthyophaga) revealed that these species contain predicted hydrophobins with unusually high proportion of acidic amino acids and therefore with potentially novel characteristics.[13] High proportion of acidic amino acids is thought to be an adaptation of proteins to high concentrations of salt.[14]
- ^ Hobley, et al. (July 2013). "BslA is a self-assembling bacterial hydrophobin that coats the Bacillus subtilis biofilm". PNAS. 110 (33): 13600–5. Bibcode:2013PNAS..11013600H. doi:10.1073/pnas.1306390110. PMC 3746881. PMID 23904481.
- ^ Sunde M, Kwan AH, Templeton MD, Beever RE, Mackay JP (October 2008). "Structural analysis of hydrophobins". Micron. 39 (7): 773–84. doi:10.1016/j.micron.2007.08.003. PMID 17875392.
- ^ Wessels J, De Vries O, Asgeirsdottir SA, Schuren F (August 1991). "Hydrophobin Genes Involved in Formation of Aerial Hyphae and Fruit Bodies in Schizophyllum". The Plant Cell. 3 (8): 793–799. doi:10.1105/tpc.3.8.793. PMC 160046. PMID 12324614.
- ^ Morris VK, Linser R, Wilde KL, Duff AP, Sunde M, Kwan AH (December 2012). "Solid-state NMR spectroscopy of functional amyloid from a fungal hydrophobin: a well-ordered β-sheet core amidst structural heterogeneity". Angewandte Chemie. 51 (50): 12621–5. doi:10.1002/anie.201205625. hdl:11858/00-001M-0000-0018-A6D2-4. PMID 23125123.
- ^ Peter Döbbeler, Gerhard Rambold (2004). Contributions to Lichenology. Gebrüder Borntraeger Verlagsbuchhandlung. p. 207.
- ^ a b Wösten HA (2001). "Hydrophobins: multipurpose proteins". Annual Review of Microbiology. 55: 625–46. doi:10.1146/annurev.micro.55.1.625. hdl:1874/13610. PMID 11544369. S2CID 38833738.
- ^ Whiteford JR, Spanu PD (April 2001). "The hydrophobin HCf-1 of Cladosporium fulvum is required for efficient water-mediated dispersal of conidia". Fungal Genetics and Biology. 32 (3): 159–68. doi:10.1006/fgbi.2001.1263. PMID 11343402.
- ^ Chen H, Kovalchuk A, Keriö S, Asiegbu FO (20 January 2017). "Distribution and bioinformatic analysis of the cerato-platanin protein family in Dikarya". Mycologia. 105 (6): 1479–88. doi:10.3852/13-115. PMID 23928425. S2CID 23984426.
- ^ Baccelli I, Comparini C, Bettini PP, Martellini F, Ruocco M, Pazzagli L, Bernardi R, Scala A (February 2012). "The expression of the cerato-platanin gene is related to hyphal growth and chlamydospores formation in Ceratocystis platani". FEMS Microbiology Letters. 327 (2): 155–63. doi:10.1111/j.1574-6968.2011.02475.x. hdl:2158/645742. PMID 22136757.
- ^ Wösten HA, van Wetter MA, Lugones LG, van der Mei HC, Busscher HJ, Wessels JG (January 1999). "How a fungus escapes the water to grow into the air". Current Biology. 9 (2): 85–8. doi:10.1016/S0960-9822(99)80019-0. PMID 10021365. S2CID 15134716.
- ^ Stringer MA, Dean RA, Sewall TC, Timberlake WE (July 1991). "Rodletless, a new Aspergillus developmental mutant induced by directed gene inactivation". Genes & Development. 5 (7): 1161–71. doi:10.1101/gad.5.7.1161. PMID 2065971.
- ^ Lauter FR, Russo VE, Yanofsky C (December 1992). "Developmental and light regulation of eas, the structural gene for the rodlet protein of Neurospora". Genes & Development. 6 (12A): 2373–81. doi:10.1101/gad.6.12a.2373. PMID 1459459.
- ^ Zajc J, Liu Y, Dai W, Yang Z, Hu J, Gostinčar C, Gunde-Cimerman N (September 2013). "Genome and transcriptome sequencing of the halophilic fungus Wallemia ichthyophaga: haloadaptations present and absent". BMC Genomics. 14: 617. doi:10.1186/1471-2164-14-617. PMC 3849046. PMID 24034603.
- ^ Madern D, Ebel C, Zaccai G (April 2000). "Halophilic adaptation of enzymes". Extremophiles. 4 (2): 91–8. doi:10.1007/s007920050142. PMID 10805563. S2CID 32590023.